Field text is shorter than specified in ABAP Dictionary

What causes this issue?

The key word (field text) on the screen should not be shorter than that
defined in the ABAP Dictionary.

How to fix this error?

Specify the text field on the screen as a variable by entering a space
or 'V' in the 'Mod' column so that the most appropriate one is
automatically used. If the shortest text field (key word) in the ABAP
Dictionary is shorter than the field on the screen, the text will be
truncated.

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